Tracheostomy tubes are used in the health care field to provide a bypass supply of air or gases to a patient having an obstruction of the larynx or pharynx and who is thus no longer able to breath through the normal route. Tracheostomy tubes are also placed in patients who, because of injury or disease, cannot breath on their own. These patients are chronically dependant on mechanical ventilation and the long-term artificial airway of choice is the tracheostomy tube.
An incision is made by the doctor below the obstruction and the tube inserted. The tube then acts as a gateway, allowing the patient to breath normally, the proximal end of the tube remaining stationary outside the trachea.
The tracheostomy tube has a tendency to become either partially or completely obstructed, over time, by the accumulation of mucus or phlegm. To resolve this problem, a system where two cannulas are placed one inside the other has been developed, which allows for the removal of the inner cannula to facilitate cleaning while still maintaining the outer cannula in the patient's trachea, U.S. Pat. No. 3,693,634 to Shiley/Mallinckrodt. Problems may occur due to accidental disconnection of the inner and outer cannulas of the tracheostomy tube, thereby allowing for spillage and/or slippage between the two. This slippage may cause a disconnection a ventilator resulting in the death of the patient.
There are several devices which contain a means of connecting the inner cannula to the outer cannula and the outer cannula to the ventilation system. These include, but are not limited to, U.S. Pat. No. 3,659,612 to Shiley et al., U.S. Pat. No. 4,009,720 to Crandall, et al. and U.S. Pat. No. 3,088,466 to Nichols. Inherent in these tracheostomy tube designs is the fact that two separate connectors are required. This means that there are two disconnection points which reduces the safety of the system, the accidental disconnection of the inner cannula with the ventilation system being increased. In addition, an air tight seal must be present between the inner and outer cannula to ensure that the respiration pressure from an artificial ventilation system is maintained and leakage does not occur. Another disadvantage is that while the inner cannula is removed, the ventilator cannot be connected to the tracheostomy tube, if needed.
U.S. Pat. No. 4,817,598 to LaBombard discloses a disposable inner cannula tracheostomy tube with a ventilator connector that is permanently fixed to the outer cannula. The proximal end of the inner cannula fits into the inner diameter of the connector and is fixed with opposing ribs and grooves that create a "SNAP" connection. The inner cannula has a proximal ring that is connected by a hinge to provide a gripping surface for removal of the inner cannula from the outer cannula.
The major problem with both the LaBombard and the Shiley devices is that they are not compatible with one another. This has created a strain on consumers in the disposable inner cannula market. What is needed is a connector device which can be used in conjunction with all the available disposable inner cannulas on the market to allow interchangability of the inner cannula with the tracheostomy tube and increase its safety. Such a connector will allow the care-giver and patient to take advantage of the product benefits of the Shiley device as well as those of the LaBombard tracheostomy tube.